Calculate Static Pressure

Calculate the amount of static pressure the fan must overcome..

Static Pressure:''

The pressure generated by fans in ductwork is typically very small. An accurate measurement of static pressure is critical to proper fan selection however. Static pressure in fan systems is typically less than2'' SP, or 0.072 Psi.

The amount of static pressure that the fan must overcome depends on the air velocity in the ductwork, the number of duct turns (and other resistive elements), and the duct length. For properly designed systems with sufficient make-up air, the guidelines in the table below can be used for estimating static pressure.

Important: Static pressure requirements are significantly affected by the amount of make-up air supplied to an area. Insufficient make-up air will increase static pressure and reduce the amount of air that will be exhausted. Remember, for each cubic foot of air exhausted, one cubit foot of air must be supplied.